Reciprocating motion device



Dec. 26, 1961 J. A. GUsTAu-'es v 3,014,459

RECIPROCATING MOTION DEVICE Filed Aug. 20, 1958 2 Sheets-Sheet 1 Dec. 26, 1961 J. A. GUSTAIRS 3,014,459

RECIPROCATING MOTION DEVICE Filed Aug. 20, 1958 2 Sheets-Sheet 2 /Z IN VEN TOR.

Patented Dec. 26, 1961 i 3,014,459 RECIPROCATING MOTION DEVICE .Iohn A. Gustairs, Royal Oak, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Aug. 20, 1958, Ser. No. 756,208 Claims. (Cl. 121-48) This invention relates to a reciprocating motion device, and more particularly to a means for obtaining a reciprocal motion through the use of a exible collapsible tube actuated by air pressure.

There have been numerous reciprocal motion devices shown and described in the past, many of them involving complicated and cumbersome linkage systems. The generally available reciprocal motion device is limited to a particular use and is usually noisy in operation. The linkages are frequently subject to failure and difficult to properly maintain in any production type usage. Mechanical linkage systems are relatively inefficient due to friction losses and space requirements.

It is here proposed to provide a reciprocating motion device which is simply constructed and has a wide adapt- Vability to production usage. The device in which this invention is embodied comprises generally a collapsible tube and a carriage which is movable in either direction along the tube through the use of air pressure. The device is relatively simple, providing ease in maintenance and repair and is highly efficient, since the speed of the device is constant and the carriage is practically frictionless in its motion along the tube, The device provides a silent reciprocating motion system, is relatively inexpensive and is adaptable to automatic operability.

In the drawings:

FIGURES l and 2 are schematic diagrams of the device in which this invention is embodied, showing the carriage in various positions valong the collapsible tube.

FIGURE 3 is a cross sectional View of the device shown in FIGURES 'l and 2 taken substantially along the line 3 3 of FIGURE 4 and looking in the direction of the arrows.

FIGURE 4 is an elevational view of the device showing the collapsible tube and the carriage assembly.

FIGURE 5 is a view of a portion of FIGURE 4 with parts broken awayand in section, and taken substantially along the line 5-5 of FIGURE 4`and looking in the direction of the arrows. Y n

Referring more particularly to the drawings, FIGURES 3, 4 and 5 illustrate the construction and location of the parts. In FIGURE 4, a collapsible tube, indicated generally by the numeral 10, is shown mounted on a rail, indicated generally by the numeral 12, and having the carriage assembly 14'engaging both the collapsible tube 10 and the rail 12. In FIGURE 5, the collapsible tube is shown in one of the many forms which could be utilized. The tube is shown comprising of a pair of lsections 16 and 18the sections being formed of rubber 20 with a canvas surface material 22. Flanges 24 are turned outwardly and adaptedrto be secured to the mating anges 26 of the lower half of the tubev 18. The canvas backing material also'extends overthe surface of the rail 13, as at 28, and is turned over the edges of the rail 13 and secured thereto by the clamping strips 30` attached to the rail 13, `as by machine screws 32. A groove 34 is provided in the lower surface ofthe rail 13, the purpose of which will be later described. a

Referring now to FIGURES 3 and 4, the carriage asl sembly consists o f a pair of spaced side plates 36 and a bottom plateS, the side plates and bottom plate enclosing the rail 12 and the collapsible tube 10. An upperl roller 40 of nylon, or any other suitable material, compresses the collapsible tube 10 against the rail 12 at its point of contact as shown in FIGURES 3 and 4. A shaft 42, passing through the side plates 36 and retained therein by the nut 44 and the lock washer 46, has a pair of ball bearing assemblies 48 mounted thereon. The bearing assemblies provide frictionless rotation of the upper roller 40 about the shaft or axle 42. A section of tubing material 50, surrounding the shaft 42, provides the proper spacing for the bearing assemblies 48 with respect to the shaft 42. Annular internal grooves S2 in the upper roller 40 receive the outer races of the ball bearing assemblies 48 to provide proper -spacing for the bearing members with respect to the roller.

A lower shaft or axle 54 passes through oblong open#1 ings 56 in the side plates 36. The shaft is secured in the side plates by the nut member 58 and properly retained therein by the washers 60. A ball bearing assembly 62 is received on the shaft 54and properly spaced thereon by the tubing sections 64 and 66. The tubing sections bear against the inner surfaces of the side plates 36 and against the inner race of the ball bearing assembly 62. The outer races of the ball bearing assemblies are received in the aforementioned groovef34 in the bottom of the rail member 12.

In order to properly adjust the rollers with respect to the rail and the collapsible tube, an adjusting block68 bears against the tube sections 64 and 66 to raise or lower the shaft 54 in the oblong openings 56. An opening 76 in the adjusting block receives the ball bearing assembly 62 and prevents interference of the block with the ball bearing assembly. A projection 72, extending from the adjusting block 68, is received in a bore 74 in the adjusting bolt 76. The bottom plate 3S of the carriage assemby has an opening 78 therethrough which is internally threaded to receive the adjustingvbolt 76. The hexagonal. head 80 ofthe adjusting bolt is attached to tit a suitable wrench and may be turned to raise or lower the adjusting block 68. A lock nut 82 also surrounds the adjusting bolt 76 to retain the parts in the proper position once they are located. y

A second shaft 84 is provided through the side plates 36 and below the rail 12. A bearing assemblysimilar to bearing 62 i-s mounted thereon/and rides in the groove 34 in the rail 12. Thus, a-three point contact is established by the carriage assembly on the rail 10 and the tube 12.

The tube 10 is secured at its ends to the"` rail 12 by the clamping blocks 816 and 88. The blocks arebolted to the rail by bolts 90. The blocks serve to close the ends of the collapsible tube and to provide a connection for air conduits 102 and 104, as illustrated in FIGURES land 2. v v

The valve assembly, which may be of a type known in the arts, shown in `FIGURES l and Zprovides the proper routing for the passage of air to-the collapsible tube. The valve assembly comprises a valve block 92 having'a pair of chambers 94 and `96 thereinV to receive the valve member 98. An airinletrconduit admitsairto the chamber. 96 and allows the passage `of air to either of the outlet conduits. 102 or 104. A passage 106 in the valve member 98 allows pasage of air from the inlet 100ftothe outlet104 when the valve member is properly positioned. The valve member is vmovedfrom one position to another through the action of air pressure, which will be later described. An opening 108m the bottom .of the valve member 98 provides communication between the conduit 102 or the conduit 164 and the exhaust conduit 110. Amore detailed operation of the valve system will also be later described. f o v A pair of air switches 116 and 114 are mounted on brackets 112,;which maybe 'secured'to the Arail 12. The

air switches are actuated by a pair of pivotal members 118 and 120 secured to the carriage assembly 14. A bracket member 122 is secured to the side plates 36 of the carriage assembly by the bolts or machine screws 124 and pivotally carries the stop members 118 and 120. Pins 126 limit the rotary motion of the stop members 118 and 120 to allow motion in only one direction.

The air switches 114 and 116 are connected to the valve block 92 through the conduits 128 and 130. The conduits communicate through the valve block with the upper chamber 9-4 and actuate the valve member 98 to move the valve member from one position to another. The air switches may consist of any conventional structure and are 'shown he-re as check valves having valve members 132 and 134. The valve members are so arranged such that incoming line pressure through the conduits 136 and 138 will be bled off through the air switch when the valve members are depressed. When the valve members 132 or 134 are actuated by the stop members 118 or 120 on the carriage assembly the air bleed will be opened and the difference in pressures between conduits 128 and 130, depending on which valve member is actuated, will slide the valve member 98 from one position to another.

The operation of the device is as fol'ows: With the parts located as shown in FIGURE 1, incoming air pressure through conduit 100 will enter the lower chamber 96 in the valve block 92. The valve member 98 is so positioned that the air must pass through the conduit 102 and into the left end of the collapsible tube 10. Since the upper and lower rollers have collapsed the tube against the -rail 12, the collapsible tube is divided into two chambers, 140 and 142. The air entering the chamber 140 will pressurize that chamber and bear against the upper roller 40 of the carriage assembly. The right end chamber 142 is allowed to exhaust through the conduit 104 into the valve block 92 and the opening 108 in the valve member 98 and from there is directed to the exhaust conduit 110. Thus the carriage assembly will be moved toward the right by the air pressure in the expanding chamber 140.

When the carriage assembly 14 reaches the air switch 116, the stop member 120 will depress the air switch valve member 134 to allow air pressure from conduit 138 to be bled'off, and the line presure in conduit 128 acting on the valve member 98 will move the valve member 93 to the left in the chamber 94. Since the air switch member 116 is in a position to bleed air to the atmosphere, there will be no opposition to the movement of the valve member 98 from right to left. The parts will now assume the position as shown in FIGURE 2.

The air inlet conduit 100 allows passage of air into the chamber 96 in the valve block 92, through the passage 106 in the valve member 98 for communication with the conduit 104 and the chamber 142 of the collapsible tube 10. The exhaust port 110 is now opened through the opening 108 in the valve member to allow chamber 140 to exhaust through the conduit 102 and into the valve block 92. The carriage assembly will thus be moved to the left, as viewed in FIGURE 2, by the action of the expanding-tube chamber 142. The stop member 120 is allowed to rotate as it passes the air switch 116 to prevent deiiection of the air switch valve member 134. The carriage assembly will continue to move to the left until the stop member 118 actuates the valve member 132 of the air switch 112. When such action takes place, the air inlet pressure through the conduit 138, the air switch 116 and the conduit 130 will force the valve member 98 to the right to begin the cycle as shown in FIGURE l.

Thus it may be seen that a relatively simple reciprocal motion is accomplished through the use of alternating air pressure and a collapsible tube. The device is suitable to a wide variety of uses and it is not proposed to restrict the invention to the specific structure as shown and described in the foregoing specification and drawings.

I claim:

- 1. In apparatus for obtaining a reciprocal motion comprising a rail, a collapsible tube secured along the length of said rail, carriage means engaging said rail and said tube and collapsing said tube against said rail at the point of engagement thereof to dene a pair of expansible chambers; the improvement wherein: said rail comprises a pair of opposite parallel surfaces, one of said surfaces having a guideway formed therein and extending longitudinally of said rail, said carriage comprising a pair of opposite parallel plates, said plates extending transversely to and outwardly beyond said opposite parallel surfaces of said rail, a cross support plate extending between Said plates to form a carriage housing and being outwardly spaced from said one sunface, first pin means extending between and supported by said plates between said cross support plates and said one sur-face, said pin means being niovably mounted in said plates for adjustment outwardly and inwardly relative to said one surface, adjustment means engageable with said pin means and extending through said cross support plate to variably position said pin means relative to said one surface, first roller means mounted on said pin 'means and being rotatably engageable within said guideway on said one surface, second pin means extending between and supported by said plate and spaced outwardly from the other surface, second roller means mounted on said second pin means and being spaced from said other surface a distance approximately equal to the collapsed thickness of said collapsible tube, said collapsible tube extending between said second roller means and said rail to divide said tube into said expansible chambers, and automatic means to alternately pressurize and depressurize said chamber for alternate expansion and collapse thereof to drive said carriage means along said rail by expansion of one of said chambers.

2. The apparatus as delined in claim l and wherein the other of said surfaces is provided wth a backing material similar to the outer material of said collapsible tube to engage said collapsible tube and prevent contact of said tube with said other surface of said rail to retard deterioration of said tube due to repeated flattening thereof between said second roller means and said rail.

3. The apparatus as defined in claim l and wherein said guideway comprises a longitudinal slot formed in said rail and said first roller means comprises an antifriction bearing having the outer race thereof received within said slot and an inner race thereof secured on said iirst pin means.

4. The apparatus as defined in claim 1 and wherein said second roller means comprises a nylon cylinder having a longitudinal bore therein, bearing seats provided at each end of said cylinder by inwardly extending counterbore portions, anti-friction bearing means mounted in each of said bearing seats and secured on said second pin means to rotatably support said nylon cylinder relative thereto.

5. The apparatus as defined in claim 1 and wherein said power means comprises air supply and valve means connected to said tube to first exhaust and secondly pressurize said chambers, said chambers when pressurized driving said carriage means in the direction of said exhausted chamber, and air switch means adjacent each end of said rail and positioned in the path of movement of said carriage means for actuation thereby to change the direction of air ow into and out of said tube to automatically change the direction of motion of said carriage means.

Conger et al. Dec. 13, 188i lPlace Apr. 28, 1896 (Other references on following page) UNITED STATES PATENTS 2,764,893 Bess Nov. 14, 1939 864,341 McCormick Sept. 22, 1942 Wilske et a1. Oct. 14, 19,47 Geiger Dec. 9, 1947 5 310,020 Lane et al. Oct. 5, 1948 740,453

Falkenberg Oct. 2, 1956 Novak Dec. 16, 1958 FOREIGN PATENTS Italy Jul. 22, 1933 Great Britain Nov. 16, 1955 

